MBBR一体式耦合短程硝化-厌氧氨氧化处理污泥水

Reject water treatment by MBBR coupled with integrated partial nitrificationanaerobic ammonium oxidation

采用移动床生物膜反应器(MBBR)处理已回收磷后的实际污泥水,在进水平均氨氮浓度为167.51 mg·L-1、HRT为22.24 h、DO为0.5 mg·L-1和温度为24~26℃的条件下实现了一体式短程硝化-厌氧氨氧化过程的耦合,对氨氮和总无机氮的最大去除率可达96%和79.7%。但是,一体式反应器受DO浓度影响较大,维持稳定的DO浓度对于系统的氮去除非常重要。荧光原位杂交(FISH)及高通量测序结果表明,MBBR的生物膜及活性污泥中Nitrosomonas菌分别占总菌数的10.46%和21.46%,厌氧氨氧化菌的优势菌种Candidatus Kuenenia在生物膜和活性污泥中分别占总菌数的4.13%和0.71%。因此,MBBR中活性污泥主要完成亚硝化,生物膜主要完成厌氧氨氧化,常温条件下,两者在一个反应体系中共同完成了对污泥水中氮的高效自养脱除。以上结果表明了一体式反应器处理实际污泥水的可行性,可为该工艺在实际工程中的应用提供参考。

A moving bed biofilm reactor(MBBR) was used to treat the reject water in which phosphorus was recovered in this study. The integrated partial nitrification-anaerobic ammonium oxidation(PNAAO) process was successfully coupled with MBBR under the room temperature of 24~26 ℃, HRT of 22.24 h, DO of0.5 mg·L-1, and the average influent ammonia nitrogen(NH4+-N) concentration of 167.51 mg·L-1. The maximum removal rates of NH4+-N and total inorganic nitrogen could reach 96% and 79.7%, respectively. However, DO concentration had a great effect on the operation of the integratd reactor. So, it is very important to maintain a stable DO concentration for nitrogen removal by the system. The results of fluorescence in situ hybridization(FISH) and high-throughput sequencing confirmed that Nitrosomonas in biofilm and activated sludge of MBBR accounted for 10.46% and 21.46% of the total bacteria, respectively. In addition, Candidatus Kuenenia was the dominant species of AAOB(anammox bacterium) in both biofilm and activated sludge, which accounted for4.13% and 0.71% of the total bacteria, respectively. Therefore, partial nitrification was mainly accomplished by activated sludge, while anaerobic ammonia oxidation was primarily accomplished by biofilm in MBBR.Therefore, the coupled process of partial nitrification and anaerobic ammonia oxidation in a MBBR could achieve an efficient autotrophic nitrogen removal under room temperature. This research shows the feasibility of the treatment of real reject water by the coupled reactor, and provides an important basis on the application of the process in practical engineering.